I’ve often been told that to preserve cut flowers for a longer time, one should dissolve some sucrose (common household sugar) in the water.
Does this also apply to potted plants? I mean, is there any benefit to putting a bit of sugar in the soil of potted plants? Can the roots absorb complex sugars directly?
No, gtowing plants make all the sugar they need from the carbon dioxide in the air. If you put sugar in the soil, you’ll just encourage the growth of yeasts, molds and bacteria. Those could damage your plants root system, and possibly kill te plant.
Not only that but you’ll invite insects to come looking for food.
Plants do need “food” but it’s minerals they need to build those sugars and other things. Interesting things occur when plants lack necessary minerals.
My favorite is manganese deficiency in certain palms. This causes a condition called “Frizzle top” which results in new leaves looking dried, stunted and burned (frizzled). Without correction the plant dies.